feat(voice-server): Add Google Cloud TTS as alternative provider

[fayerman-source]

Summary

Adds Google Cloud Text-to-Speech as a second TTS backend alongside ElevenLabs:

• Provider selection via settings.json → daidentity.ttsProvider ("elevenlabs" or "google-cloud")
• Backwards compatible — defaults to ElevenLabs when ttsProvider is not set
• No new dependencies — uses Google's REST API directly via fetch (no SDK)
• Configurable voice via daidentity.googleCloudVoice (language, voice name, type, rate, pitch)

Why Google Cloud TTS

• Free tier: 4M characters/month (Standard) or 1M (WaveNet) vs ElevenLabs' 10K
• No attribution requirement on the free tier
• Good fallback when ElevenLabs quota runs out

Configuration

Add to ~/.env:

GOOGLE_CLOUD_API_KEY=your_key_here

Add to ~/.claude/settings.json:

{
  "daidentity": {
    "ttsProvider": "google-cloud",
    "googleCloudVoice": {
      "languageCode": "en-US",
      "voiceName": "en-US-Neural2-D",
      "voiceType": "NEURAL2",
      "speakingRate": 1.0,
      "pitch": 0.0
    }
  }
}

Or keep using ElevenLabs by not setting ttsProvider (or setting it to "elevenlabs").

Files Changed

• Releases/v3.0/.claude/VoiceServer/server.ts — Multi-provider TTS routing, Google Cloud TTS implementation

Context

This is a re-implementation of PR #285 (merged 2026-01-01, lost in v3.0 restructuring) targeting the current v3.0 architecture. The original code lived in Packs/kai-voice-system/ which no longer exists.

Closes #682

[kaimagnus]

Nice addition of Google Cloud TTS! This has merge conflicts with recent VoiceServer changes (commit 95d65cc). Could you rebase on main? We'll merge once the conflicts are resolved. Thanks! 🙏